Meteor Imposter
June 04, 2005
Provided and copyright by: Andrew Yee, ZINC Projects
Summary authors & editors: Andrew Yee
No, this is not a picture of a brilliant fireball meteor. The above photo shows the second half of an Iridium satellite flare, as visible from Britt, Ontario, Canada on 15 April 2005 (at 11:10 p.m. Eastern Daylight Time or 03:10 UTC on 16 April).
According to the satellite tracking website Heavens-Above (see below), this flare was from the Iridium 34 satellite, which was moving from the lower left to the upper right on the above photo. The upper end of the flare track points to Vega, the brightest star in the constellation Lyra (The Lyre). Adjacent to the foreground tree on the left is the bright star Deneb, the brightest star in the constellation Cygnus (The Swan). This particular flare reached a maximum brightness of about magnitude -6 ,which is even brighter than Venus at its maximum brilliancy.
A constellation of 72 Iridium satellites (66 operational and 6 backups) orbit the Earth in six different orbital planes, at an altitude of 780 km (487 mi), providing global telecommunications services. On each of the Iridium satellites three are Main Mission Antennae (MMA), the communication antennae. These MMA have a highly reflective aluminum surface coated with a layer of silvered teflon. When the antenna "catches" sunlight, it casts a sharp, narrow cone of light towards the ground. An observer within this cone (several kilometers in width) can see the mirror like reflection (specular) as a bright streak of sunglint (a flare), a magnitude up to about -8, lasting a second or two in duration.
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